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MrSeb writes "An international team of engineers, physicists, and chemists have created the first fiber-optic solar cell. These fibers are thinner than human hair, flexible, and yet they produce electricity, just like a normal solar cell. The U.S. military is already interested in weaving these threads into clothing, to provide a wearable power source for soldiers. In essence, the research team started with optical fibers made from glass — and then, using high-pressure chemical vapor deposition, injected n-, i-, and p-type silicon into the fiber, turning it into a solar cell (abstract). Functionally, these silicon-doped fiber-optic threads are identical to conventional solar cells, generating electricity from the photovoltaic effect. Whereas almost every solar cell on the market is crafted out of 2D, planar amorphous silicon on a rigid/brittle glass substrate, though, these fiber-optic solar cells have a 3D cross-section and retain the glass fiber's intrinsic flexibility. The lead researcher, John Badding of Penn State University, says the team has already produced 'meters-long fiber,' and that their new technique could be used to create 'bendable silicon solar-cell fibers of over 10 meters in length.' From there, it's simply a matter of weaving the thread into a fabric."

Forget your phone, this could provide endless power for medical devices from insulin pumps to more exotic things like replacement limbs and those artificial eyes that are getting better each year (you get to see a 12x12 pixel image now! wooo, shiney). One of the problems with medical devices is finding a continuous power supply.

It won't - not enough power from solar cell even if you convert 100% of your surface area in a perfect light. Napkin calculation tells me it would take 48 sunlight to recharge your typical smartphone battery in ideal circumstances.

A solar panel produces 8-10 watts per square foot. A smartphone while charging (with the screen off) typically draws no more than 500 mA at 5VDC, or about 2.5 watts. Some support faster charging at up to an amp. Either way, it requires nowhere near your entire surface area; with traditional PV cells, a typical adult could produce that much power with just one sleeve in full sun, give or take.

An interesting implementation would be an entire piece of clothing like a hat entirely woven with this material. One weakness of traditional PV cells is the angle it faces the source (the sun). A perpendicular angle to the source achieves maximum results, being circular allows to capture light at different angles to the source much more efficiently.

First thing I thought of too, but makes me wonder how flexible this would be, could it be folded? How about ironed and washed without damage? No idea about fiber optics (a minute on Google didn't help) but those seem to be pertinent questions before it's ready to be integrated into clothes.
The whole multi-angle light collection seems like it could be pretty useful as well.

Just curious, how much energy would it generate given the surface area of power lines strewn along light poles for hundreds of miles.. Would it over those lengths generate enough energy to juice those power lines and power a grid? Or at least to help power it?

I think we are barreling off toward the silly on the ideas front, but if you restrict it to HV-DC lines, a single cell usually puts out.5-.6 VOC, so you just need to string 400,000 of them together and voila, you are pushing power in. That has to be seriously small surface area even aggregated across miles of line. Anyone want to do the math?

If we assume a 15cm diameter power cable (which means a 15cm effective width; sure, the actual cable circumference is more than that but half of it's out of the sunshine and the rest isn't all perpendicular), a one kilometer length of cable would have a 'collection area' of 150m^2. Given full-time sunshine (dicey) and 40% efficiency of conversion (roughly state of the art, iirc) that one kilometer cable will generate about 84 kW. Assume that an average day has about 6 hours of full sunshine (wild-ass guess)

Power from sun = Direct Current, power lines = Alternating Current. Not the same and no help.

Our country made the decision long ago to not pursue DC as our power supply. Power from photovoltaic cells creates a stream of electricity in one direction. The conversion and voltage (very high along power lines) makes it a fun idea, but not practical.

The problem is not converting it, the problem it doing so over and over on millions of miles of power lines...enough to make it of any value. This is not to mention the difficulty of replacing or covering all of the lines and then converting the power to much, much higher voltage A/C when the amperage is very low coming from the pv.

My point wasn't that you can't covert AC to DC and back, the point is that it is not simply putting up a PV cell and plugging it into the power lines. Make sense?

Today, anybody can afford to board a high speed aircraft and travel at 350 MPH at 40,000 with safety that rivals our living rooms. Think about that. A chair, 40,000 feet in the air, travelling 350 MPH, affordable to nearly everybody, complete with magazines to read, and we mostly complain about the noise.

> Approximately half of all the generating capacity last year was from renewable energy sources. [kcet.org]

Misquote. From the article you linked to,

According to the Federal Energy Regulatory Commission (FERC), renewable energy projects -- including solar, wind, hydroelectric, geothermal and biomass -- made up almost half of all new power generation installations in the U.S. in the first 10 months of 2012. (Emphasis mine.)

That's WAY different from "approximately half of all generating capacity" which wo

How would something like this hold up under real world use? Clothing is bent and folded, individual fibers are often pinched very tightly and broken. Since electricity requires a closed circuit, wouldn't a break and a fiber render that fiber useless for producing electricity?

Everyone is speculating about how this could be used in clothing, but I think this is the wrong use case. Clothing has too little sun facing surface area to produce the amounts of electricity to be more useful than existing battery tech.

However, the military uses a lot of cloth in large sun facing swaths. Ever seen a tent city? Tents are the perfect use case for this tech. Large surface areas, can be oriented towards the sun, rarely washed, never ironed, and only folded up for transport or storage. Integrating the solar tech into the fabric instead of an extra add on package would be ideal.

A more mundane use would be things like car or RV covers. Cover the rig, plug the cover into a smart battery charger, walk off.

Even more simple, just something to toss over a roof and fasten into place with double-sided tape (perhaps Velcro.) The result would be useful power, but without sacrificing repairability, other than the added weight.